The long-term objective of this application is to develop a wearable multi-sensor way finding device for the visually impaired that can function reliably both indoors and outdoors. The Phase I specific aims are to: 1) assemble and test a hardware platform that consists of a pocket-size computer and 4 sensors: a wireless signal receiver inside a wearable computer, a pedometer, a GPS receiver, and a digital compass; 2) implement and test sensor fusion algorithms that fuse data from the 4 sensors both indoors and outdoors; and 3) develop an unobtrusive mechanical package that will enable the wear ability, durability, and extended use. The project is relevant to the NIH mission, because its long-term objective addresses a fundamental need of the target population: the ability to navigate dynamic and complex indoor and outdoor environments with comfort and ease. In particular, the project will give a new way finding technology to visually impaired and blind students that will improve their access to university and college campuses. The Phase I R&D will include 3 major steps: 1) To design and develop a wearable way finding hardware platform that consists of a single board computer and 4 sensors; 2) To implement and a Markov Localization sensor fusion framework for indoors and outdoors; 3) To develop a detailed mechanical design based upon the hardware platform that will enable device wear ability, durability, and extended use. The methods will consist of iterative hardware design, sensory data collection, testing of sensor fusion algorithms with respect to localization accuracy, and 3D computer aided design (CAD). This research is relevant to public health, because the proposed way finding technology will enable visually impaired navigators to safely navigate unfamiliar environments and avoid accidents caused by lack of vision. [unreadable] [unreadable] [unreadable]